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bnf: SoC: 54%
Calibration needed: 0
Hildon: Battery low
These contradictions are tiresome...
Best wishes.

Out of curiosity, which one was "right"? What was battery voltage at the moment?

I can say that there were many instances of the battery indicator recovering from red "battery low" to green "half-charged" without any actual charging involved. Therefore, I expect that a misinterpretation of battery characteristics is taking place.
What do "IMIN: 1" and "VDQ: 1" mean? And is it possible for a BL-5J battery to have "Charge: 1529 mAh"? With USB cable charging, it reports "Voltage: 4166 mV", "Current: 12 mA".
Thank you. Best wishes.

IMIN:1 means, that it have reached last stage of charging/charging is practically finished (current accepted by battery is less than 100 mA, might be as well device power usage). VDQ:1 means "valid discharge quality", i.e. since last full charge (even if it just ended), discharge wasn't interrupted to the point of spoiling discharge measurement, so upon reaching edv1, new battery calibration data might get saved.

All those things are explained in calibration post, linked in my signature

As for 1500 mAh - depending on your usage pattern, relative capacity might be around 1500 mAh, but it is unlikely to seen for any variant of genuine Nokia's BL-5J. OTOH, for Scud's or Polarcells, relative capacity of 1700 mAh isn't anything surprising.

/Estel

Thank you. I am still using the original BL-5J which came together with Nokia N900 three years ago. If battery problems become too persistent, I will probably buy Polarcell. I am using wires too frequently to be concerned about battery charge, at this moment; six hours is the longest time it would have to survive without charging.
Best wishes.